Electrooptical wide-angle beam deflector based on fringing-field-induced refractive inhomogeneity in a liquid crystal layer

A controllable, refractive, electrooptical liquid crystal (LC) beam deflector has been studied both theoretically and experimentally. The principle of operation of the deflector is based on the generation of a high gradient of refractive index in a thick LC layer by the fringing field between two lateral electrodes in a simple 3-electrode LC cell. A Gaussian laser beam, focused into the narrow region at the electrode gap was effectively deflected by the refractive index gradient. Large deflection angles of ∼15° as well as a high deflection efficiency of 98% were demonstrated experimentally backed by a theoretical analysis.